I've been asked this so many times now, that I thought I'd post an explanation, as most people really can't believe that they do work! Anyway, here's how. Hope it helps some of you

Wool is absorbent, but absorbs very slowly. Because of the body heat of your baby, and the warmth of the wool, it also allows wet to evaporate, and this happens at the same rate as it absorbs. When evaporation takes place, the wet is turned into gasses. Most people think this will be steam, but in fact it's not. Steam is created when evaporated water condenses again, and this happens when the air containing the evaporated gasses, hits something cold, and there is enough wet in it to saturate the air. (This is called the dew point).

If you have a PUL wrap, the inside of the PUL will not let the wet get any further, so the evaporated gasses build up inside the PUL, and also because PUL has a cold feel, the saturated air will cause wet to condense again, and get absorbed back into the nappy. This doesn't happen with wool, because it is warm, and can breath, so "dew point" is never reached, and the gasses continue one their journey, unrestricted by the wool , baby clothes, bedding etc. It will finally condense possiby when it hits the window of your baby's room in winter, but basically the amount of wet in the air never gets high enough to reach dew point.

This evaporation also causes cooling in your baby, and that's why wool nappy covers keep your baby cooler than PUL.

Wool and lanolin are both self cleaning and anti-bacterial, and that's why wool nappy covers don't need washing unless they actually get grubby or soiled. They just need hanging up to air, and allow the lanolin in them to do its' work.

Re lanolising every few weeks, keeps the waterproofing and self cleaning properties in tip top condition. It is a simple procedure, although freshly lanolised wool will take a little longer to dry than just washing it.

Thanks for this - we have a couple of wool soakers now and I love them and recently was told that you can relanolise them with some lansinoh, about a pea sized amount (we have spare, yay!) and a tbsp of hot water and about 1/2 a tsp of baby wash then mix it and tip this in to a bucket of water and swirl the nappies around. Does this sound like it'll work? Really pleased if so, means i don't have to buy lanolin

I totally agree... couldn't believe it would work. I had to see it to believe. Now I am a convert

I love my wool shorties, bought them pre loved from here and i am looking to buy some longies but not sure what type of wool to buy or where to get new ones? I really want some soft wool as the shorties i have are really thick and well felted but they do leave marks around his legs. Anyone with suggestions please xxx

So is it just water that's evaporating and the "impurities" (urea, uric acid etc) stay as crystals or something in the nappy/wrap? Like when you boil salt water and the salt stays behind?

Yes you can use lansinoh fine for laonolizing nappies. Your method sounds mostly OK as well, but only dilute the emulsified lanolin enough to just cover what you are lanolizing - don't fill the bucket. And I always allow them to soak overnight - the wool needs time to soak up the lanolin - a quick swish will not allow it to absorb very much.

I did think the quick swish part sounded off! Lovely, thank you

Oooh think I might take the plunge and try some wool as it sounds so good and looks lovely! xx

Yay! You've got it in one! That's exactly it. Couldn't have described it better myself !

Took the plunge with wool! Bought 2 lovely custom soakers and they are lanolizing as I type! I'm trying the same method Rwhite was talking about. Hopefully they will be all set to go tomorrow when my fitteds arrive in the post! I'm excited